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Integration of life cycle assessment (LCA) and modeling methods in investigating the yield and environmental emissions final score (EEFS) of carp fish (Cyprinus carpio) farms 全文
2021
Marzban, Afshin | Elhami, Behzad | Bougari, Eisa
This study was conducted to investigate and predict the yield and environmental emissions final score (EEFS) of common carp fish farms in Shushtar county of Khuzestan province. The required data was collected from 115 carp fish farms selected by random sampling using face-to-face questionnaire and interview. The total input energy, the yield, and energy ratio were obtained as 293,127.95 MJ ha⁻¹, 3389.28 kg ha⁻¹, and 0.30, respectively. Electricity and feed consumption had the highest contributions to total input energy and environmental emissions. The normalization results showed that the marine aquatic ecotoxicity (MAET) and freshwater aquatic ecotoxicity (FAET) had the highest values among all impact categories with 671.50×10⁻⁹ and 152.60×10⁻⁹, respectively. Also, the EEFS was calculated per tons of carp fish as 7793.09 pPt. The comparison of results between the regression model and adaptive neuro-fuzzy inference system (ANFIS) indicated that in prediction of the yield, the accuracy values (R²) of regression and ANFIS models were 0.87 and 0.99, respectively, while in prediction of EEFS, R² of regression and ANFIS models were 0.98 and 0.99, respectively. In total, it was concluded that ANFIS model can predict the yield better than regression model.
显示更多 [+] 显示较少 [-]Investigating the spatiotemporal variability and driving factors of China’s building embodied carbon emissions 全文
2021
Bai, Jing | Qu, Jiansheng
Rapid and large scale construction activities consume significant resources and make impacts on the environment. To support policy for emission reduction and route of low-carbon society development, this paper estimated building stocks and building embodied carbon emissions (BECEs) in China’s 31 provinces from 1997 to 2016 by material flow analysis (MFA). Furthermore, global and local Moran’s indices were employed to investigate the geographical clustering patterns, and temporal and spatial decomposition models were proposed to identify the driving forces. The results reveal the total BECEs has boomed from 9.67 billion tons in 1997 to 28.99 billion tons in 2016. BECEs in 31 provinces have experienced consistent increase but obvious differences in growth rate, and are spatially inclined to decrease from eastern coastal regions to western inland regions. The change of spatial agglomeration pattern is complex and variable. It presents that a long and narrow “H-L agglomeration” is located in the two northernmost provinces and the other 29 provinces enforce a sequence arrangement with an order of “H–H”, “L–H”, “H–L”, and “L–L” from east to west. Temporal decomposition results show that investment scale, economic level, and population density are the main driving forces for the increase of BECEs from both national and provincial levels, while the main reasons for the decrease are technical level and return on investment. Spatial decomposition results demonstrate that population density and provincial area are the main driving forces for the difference between provincial and national average, and others cause the difference among provinces.
显示更多 [+] 显示较少 [-]Performance evaluation of a decentralized rooftop solar photovoltaic system with a heat recovery cooling unit 全文
2021
Duraivelu, Revati | Elumalai, Natarajan
The present work represents a detailed performance analysis of a 5-kWₚ on-grid solar photovoltaic rooftop system installed on a flat roof of a hospital building at a height of 12 m from the ground level, located at Perambalur (latitude 11° 23′ N and longitude 78° 93′ E), Tamilnadu, India. The daily, monthly and annual average performance parameters of the PV system including energy output, final yield, reference yield, array yield, photovoltaic array efficiency, system efficiency, inverter efficiency, performance ratio and capacity utilization factor have been analysed. The environmental benefit analysis and the payback period of the installed solar photovoltaic plant are also discussed. This solar photovoltaic power plant generates around 7144 kWh per annum of electrical energy, which is fed into the grid, and the annual average array, inverter, system efficiency, capacity utilization factor and performance ratio of the plant are found to be 12.15%, 97.12%, 11.72%, 16.31% and 76.83%, respectively, during the year 2019. The overall PV module electrical efficiency has been increased by 1.21% by applying the forced air circulation mechanism and 2.31% by applying the forced water circulation mechanism. Subsequently, the heat gained by the system can be utilized for heat load application. The installed solar photovoltaic power plant has a positive impact on greenhouse gas emissions with a reduction of 11.287 t of CO₂, 8.86 kg of SO₂, 18.50 kg of NOₓ and 485.792 kg of ash per annum. The water-based cooling in photovoltaics can potentially generate an output energy of 7310 kWh, which is relatively higher than the energy generated by the photovoltaic module with air cooling.
显示更多 [+] 显示较少 [-]Molecular and cellular responses to short exposure to bisphenols A, F, and S and eluates of microplastics in C. elegans 全文
2021
Ficociello, Graziella | Gerardi, Valentina | Uccelletti, Daniela | Setini, Andrea
Bisphenol F (BPF) and bisphenol S (BPS) have been developed as an alternative to bisphenol A (BPA), a well-known endocrine disruptor, leading to their detection in the aquatic environment. In this work, we used the animal model Caenorhabditis elegans to improve our understanding of their potential effects on the biota and the environment. Our findings demonstrated that, after 24 h exposure, all the bisphenols examined increased the number of apoptotic corpses and the expression of the detoxifying enzymes SOD-3 and GST-4, without affecting the ROS levels, while BPA and BPS significantly enhanced DNA fragmentation. Furthermore, similarly to BPA, BPF and BPS did not alter the lifespan through the activation of SEK-1 and SKN-1 pathways. Thus, this study raises the attention of the risks associated with exposure to BPA alternatives. We also examined the effects of microplastic (MP) eluates on C. elegans. Aqueous extracts of weathered microplastic samples, both at high and low degradation state and pellets, have been evaluated for their effects on lifespan, DNA fragmentation, germline apoptosis, and oxidative stress response. Overall, our findings showed that eluates of low degraded plastics exert a greater toxic effect on the nematode C. elegans compared with the aqueous sample of high degraded plastic fragments and pellets.
显示更多 [+] 显示较少 [-]Sources and reporting of oil spills and impacts on wildlife 1970–2018 全文
2021
Chilvers, B. L. | Morgan, K. J. | White, B. J.
The extraction, transport, and consumption of hydrocarbons occur daily worldwide and can lead to environmental pollution and significant incidents of wildlife mortality. This review of literature and publicly available databases from 1970 to 2018 summarises records on oil spill incidents, sources of spills, and reported effects on wildlife. During this time period, millions of tonnes of oil were released from over 1700 acute oil spills, with only 312 (18%) reporting wildlife effects. The most numerous reported spill source was shipping. From this review, there are obvious global gaps in reporting of oil spills and recording of effects on wildlife. We recommend there is a global need for increased consistency of reporting and availability of data of oil spills, and wildlife impacts. This information is critical to preparedness and response procedures for industry (shipping and oil) and governments.
显示更多 [+] 显示较少 [-]Beneficiary of nitrifying bacteria for enhancing lettuce (Lactuca sativa) and vetiver grass (Chrysopogon zizanioides L.) growths align with carp (Cyprinus carpio) cultivation in an aquaponic system 全文
2021
Ajijah, Nur | Apriyana, Arina Yuthi | Sriwuryandari, Lies | Priantoro, Ekaputra Agung | Janetasari, Selly Ayu | Pertiwi, Tanti Yulianti Raga | Suciati, Ajeng Maryam | Ardeniswan, | Sembiring, Tarzan
The aquaponic system is an alternative strategy to treat aquaculture waste and achieve food independence. Bacteria play vital roles in the aquaponic system as they can transform ammonia or ammonium into nitrite and then into nitrate, which is more favorable for bacteria, fish, and plants. The objective of this study was to determine the effect of nitrifying bacteria (Nitrosomonas europaea Winogradsky and Nitrobacter winogradskyi Winslow) on the aquaponic system in terms of water quality, nutrient availability, and productivity of carp (Cyprinus carpio), lettuce (Lactuca sativa var. crispa), and vetiver grass (Chrysopogon zizanioides L.). The experiment consisted of four treatments: aquaculture of carp as a control for fish (A), hydroponic of lettuce and vetiver grass without nutrient addition as a control for plants (B), aquaponic (carp, lettuce, vetiver grass) (C), and aquaponic with nitrifying bacteria addition (D). The results showed nitrifying bacteria addition had a significant effect on daily growth rate (DGR) and relative growth rate (RGR) of lettuce within a treatment; on the other hand, the nitrifying bacteria did not give a significant effect to RGR of vetiver grass. The growth rate, specific growth rate, and survival rate of the carp in aquaculture treatment (A) were lower than in both aquaponic treatments (C and D). Nitrifying bacteria addition in the aquaponics system had a significant effect of increasing the orthophosphate concentration. Water quality was also indicated to be better in the aquaponic system than in the aquaculture system. The integration of aquaculture and hydroponics with the addition of nitrifying bacteria enables the formation of microorganism communities, nitrate, and orthophosphate, which lead to the improvement of water quality, nutrient availability, and plant growth.
显示更多 [+] 显示较少 [-]Research on the effects of diesel engine exhaust transport distance on particulate microstructure 全文
2021
Zhao, Yang | Li, Mingdi | Xu, Guangju | Lichuanjushi, | Yuan, Yinnan | Wang, Zhong
This study aims to reveal the evolutionary process of particles during the diesel exhaust transport process and to further understand the effects of diesel exhaust transport distance (DET) on a particulate microstructure. Specifically, the micromorphological, particle size distribution, and aggregate characteristics of particles as well as the variation of the structural characteristics of elementary carbon particles (ECPs) as DET changed were examined using an engine exhaust particle size spectrometer, a high-resolution transmission electron microscopy system, and a small-angle X-ray scattering system. The results show the following: As DET increased, the chains gradually lengthened, the extent of accumulation and stacking increased, and a number of clusters gradually rose. The average particle diameter increased from 23.1 nm at 0 m to 92.7 nm at 3 m. In addition, as DET increased, the number of accumulation-mode particles, the number of folded, curved carbon layers in the inner core of carbon particles, and the disorderliness of carbon layers in the outer shell of carbon particles all increased. Moreover, the boundary between the inner core and the outer shell became increasingly obscure. As DET increased, there was a gradual decrease in the difference in electron density between particles, and the fractal dimensionality of the distribution, average cross-sectional size, radius of gyration, and axial length of pores were, respectively, 33.3%, 40%, 38.2%, and 50.3% less at 3 m than at 0 m. Besides that, the number of small (< 3 nm) pores gradually increased, and the number of large (> 10 nm) pores gradually decreased. Overall, as DET increased, pore size and number decreased. There was a gradual increase in the number of folded and curved carbon layers in the inner core of ECPs and an increase in the disorderliness of carbon layers in their outer shell as DET increased. Furthermore, the boundary between the inner core and the outer shell became increasingly obscure as DET increased. The crystallite size of ECPs decreased from 1.365 nm at 0 m to 1.098 nm at 3 m. This suggests that the number of continuously arranged carbon atoms decreased, the arrangement of carbon atoms was more disorderly, and the degree of graphitization decreased. As DET increased, there was a gradual increase in the interlayer spacing and curvature of ECPs. This suggests that increasing DET led to a more disorderly distribution of electron orbitals inside the carbon layers, less electron resonance stability in the carbon layers, greater oxidative activity of ECPs, and greater inherent oxidative capacity of particles.
显示更多 [+] 显示较少 [-]The dynamic role of institutional quality, renewable and non-renewable energy on the ecological footprint of OECD countries: do institutions and renewables function as leverage points for environmental sustainability? 全文
2021
Christoforidis, Theodoros | Katrakilidis, Constantinos
This article examines for the first time the impact of disaggregated energy sources and institutional quality on the ecological footprint (EF) of 29 OECD countries, by explaining how the diversification in countries’ energy mix and their institutional performance are associated with sustainable environmental performance. We use panel data from 1984 to 2016 and we apply second-generation techniques to arrange the critical issues of cross-sectional dependence and heterogeneity. The applied cointegration tests expose a long-run equilibrium relationship that associates renewable/non-renewable energy consumption, economic growth, institutional quality, and the EF of OECD countries. The robust cross-sectional augmented distributed lag (CS-DL) estimator shows that economic growth and the adoption of non-renewable energies are detrimental to the environment, while the operational quality of institutions adds to ecological sustainability. Concurrently, the negative effect of renewables on EF does not seem to cause a significant beneficial impact on the environment. Moreover, there is evidence that non-renewable energy and institutional quality have a bidirectional causal association with EF. Also, a weak unidirectional causal effect is running from the EF to renewables consumption. The study further demonstrates the inefficient integration of renewable energy forms in OECD countries and the concomitant essential role of institutions on environmental sustainability by providing relevant policy orientations.
显示更多 [+] 显示较少 [-]Paper-based electrochemical sensor for on-site detection of the sulphur mustard 全文
2021
Herein, we report a novel paper-based electrochemical sensor for on-site detection of sulphur mustards. This sensor was conceived combining office paper-based electrochemical sensor with choline oxidase enzyme to deliver a sustainable sensing tool. The mustard agent detection relies on the evaluation of inhibition degree of choline oxidase, which is reversibly inhibited by sulphur mustards, by measuring the enzymatic by-product H₂O₂ in chronoamperometric mode. A nanocomposite constituted of Prussian Blue nanoparticles and Carbon Black was used as working electrode modifier to improve the electroanalytical performances. This bioassay was successfully applied for the measurement of a sulphur mustard, Yprite, obtaining a detection limit in the millimolar range (LOD = 0.9 mM). The developed sensor, combined with a portable and easy-to-use instrumentation, can be applied for a fast and cost-effective detection of sulphur mustards.
显示更多 [+] 显示较少 [-]Construction land suitability assessment in rapid urbanizing cities for promoting the implementation of United Nations sustainable development goals: a case study of Nanchang, China 全文
2021
Cities, the main place of human settlements, are required to offer high-quality environments to citizens. To achieve this, it is essential to overcome several mega challenges of urbanization, population growth, economic development, environmental deterioration, and climate change. Urban infrastructure construction is capable of enhancing economic growth and promoting urban sustainability, while it will lead to many environmental problems if the infrastructure construction is not properly planned and designed. To address this challenge, this study aims to understand how to ensure the construction land expansion sustainably in rapidly urbanizing cities. In particular, this study analyzed the suitability of construction land expansion in Nanchang, a rapid urbanizing city in China, from 1995 to 2015. The results indicate that the urban expansion speed from 1995 to 2005 was faster than that from 2005 to 2015. The construction land in Nanchang was expanding towards “all directions” and sprawled towards surrounding districts and counties from the original core areas. Nevertheless, about 70% of the Nanchang area was allowable construction area (highly suitable expansion, relatively suitable expansion, and basically suitable expansion areas), indicating that the abundant reserved land resources for urban construction. This study also identified multiple suitability expansion paths of construction land, providing a scientific guidance for the land use planning of Nanchang city. Overall, this study provides a reference to the understanding of the construction land expansion for the achievement of United Nations sustainable development goals. It can also promote the understanding of spatial territory planning and practically enhance the capabilities of land use planning and design.
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